# US 12,179,420 B2 · Powder and method for the preparation of three-dimensional objects > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,420 B2 - Document ID: US12179420B2 - Status: Granted - Kind: B2 - Application number: 17/624,659 - Filed: 2020-07-06 - Published: 2022-09-01 - Granted: 2024-12-31 - Earliest claimed: 2019-07-05 - Assignees: Friedrich-Alexander-Universität Erlangen-Nürnberg - Applicants: Friedrich-Alexander-Universität Erlangen-Nürnberg - Inventors: Nicolas Vogel; Herbert Canziani - Web page: https://patentgrep.com/patent/US12179420B2 ## CPC - B29C 64/153: using layers of powder being selectively joined, e.g. by selective laser sintering or melting - B01J 2/04: in a gaseous medium {(if combined with suspending the material in a gas, e.g. fluidised beds B01J2/16)} - B22F 1/052: characterised by a mixture of particles of different sizes or by the particle size distribution - B22F 1/10: Metallic powder containing lubricating or binding agents; Metallic powder containing organic material - B29B 9/10: by moulding the material, i.e. treating it in the molten state - B29B 9/12: characterised by structure or composition - B33Y 10/00: Processes of additive manufacturing - B33Y 70/00: Materials specially adapted for additive manufacturing - B33Y 70/10: Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials - B33Y 80/00: Products made by additive manufacturing - B29B 2009/125: {Micropellets, microgranules, microparticles} - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - B29B: PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING ## Abstract The present invention relates to a powder for the preparation of three-dimensional objects comprising, or consisting of, supraparticles (8,9,10) comprising at least a first population of first primary particles, wherein the first primary particles are thermoplastic polymeric particles, wherein the first primary particles have a volume-averaged median particle diameter of from 10 to 2000 nm; wherein the primary particles are agglomerated and/or partially sintered together to form the supraparticles, and/or wherein the supraparticles have a volume-averaged median particle diameter of from 2.5 to 100 pm. The invention also relates to a method for preparing in a powder for the preparation of three-dimensional objects comprising a1) providing an at least first population of first primary particles in a first dispersion medium, thereby forming a first dispersion (1); and/or a2) providing an at least second population of second primary particles in a second dispersion medium, thereby forming a second dispersion (2); and/or a3) mixing the first dispersion and the second dispersion, thereby forming a mixture (3) of the first and second dispersion; and b) atomizing (5) the first, second or mixture of the first and second dispersion thereby forming droplets of the first, second or mixture of the first and second dispersion; and c) removing all dispersion media, preferably evaporating all dispersion media by spray drying (7), thereby obtaining supraparticles (8,9,10). ## Claims ### Claim 1 A powder for the preparation of three-dimensional objects comprising, or consisting of, supraparticles comprising at least a first population of first primary particles, wherein the first primary particles are thermoplastic polymeric particles, wherein the first primary particles have a volume-averaged median particle diameter (x50,3) of from 20 to 1000 nm, wherein the primary particles are agglomerated and/or partially sintered together to form the supraparticles; wherein the first primary particles have a spherical or at least approximately spherical shape, and at least a second population of second primary particles, whereby the second primary particles are selected from the group of organic particles, inorganic particles or combinations thereof, wherein the second primary particles have a volume-averaged median particle diameter (x50,3) of from 10 to 2000 nm, wherein the second primary particles are homogeneously distributed within the supraparticles, the second primary particles form a radial gradient within the supraparticles, the second primary particles are located in the core of the supraparticles or the second primary particles are located on the surface of the supraparticles; and wherein the second primary particles and the first primary particles are made of different materials; and wherein the supraparticles have a volume-averaged median diameter (x50,3) of from 4 to 60 μm, wherein the span of the particle size distribution of the supraparticles calculated according to the following formula span = x 90 , 3 - x 1 ⁢ 0 , 3 x 5 ⁢ 0 , 3 ( Eq . 2 ) is in the range of 0.7 to 2.5 and wherein the supraparticles have a spherical or at least approximately spherical shape, and wherein the supraparticles have a surface roughness of half the volume-averaged median particle diameter (x50,3) of the first primary particles and lower; or wherein the powder has a tensile strength of 20 Pa or less. ### Claim 2 (depends on 1) The powder for the preparation of three-dimensional objects according to claim 1, wherein the supraparticles comprise at least a second population of second primary particles, whereby the second primary particles are selected from the group of thermoplastic organic particles, duroplastic organic metal particles, metal oxide particles, transition metal oxide particles, metal salt particles, ceramic particles, silicate particles, silica-based particles, zeolites, glass particles, metal organic frameworks, carbonaceous particles, particles formed from two dimensional, sheet-like structures, or combinations thereof, wherein the second primary particles have a volume-averaged median particle diameter (x50,3) of from 20 to 1000 nm. ### Claim 3 (depends on 1) The powder for the preparation of three-dimensional objects according to claim 1, wherein the Hausner ratio of the powder is below 1.50; and/or wherein the angle of repose of the powder is 45° or less; and/or wherein the powder has a tensile strength of 10 Pa or less; and/or wherein the span of the particle size distribution of the supraparticles is in the range of from 0.8 to 2.0. ### Claim 4 (depends on 1) The powder for the preparation of three-dimensional objects according to claim 1, wherein the first primary particles comprise at least one thermoplastic homo- and/or copolymer selected from the group of polyolefins, polyamids, polyvinylic polymers, polycarbonates, polyacrylates, poly methacrylates, polyesters, polyurethanes and combinations thereof. ### Claim 5 (depends on 1) The powder for the preparation of three-dimensional objects according to claim 1, wherein the first primary particles comprise a biodegradable polymer. ### Claim 6 (depends on 2) The powder for the preparation of three-dimensional objects according to claim 2, wherein the diameter of the second primary particles is equal or less than the diameter of the first primary particles; or wherein the diameter of the second primary particles is bigger than the diameter of the first primary particles; or wherein the surface coverage of the second population of primary particles on the supraparticle surface is from 1% to 95%. ### Claim 7 (depends on 1) The powder for the preparation of three-dimensional objects according to claim 1 wherein the first primary particles and the second primary particles are combined in a mass ratio of from 1:1 to 1000:1; and/or wherein the supraparticles further comprise antioxidants, pigments, fillers, stabilizers, pharmaceutically active substances, antimicrobial substances or combinations thereof; and/or wherein the powder for the preparation of three-dimensional objects is an additive manufacturing powder; and/or wherein the shell thickness of a composite supraparticle with core shell morphology is from 100 nm to 10 μm. ### Claim 8 (depends on 1) The powder for the preparation of three-dimensional objects according to claim 1, wherein the primary particles are agglomerated by physical forces and/or partially sintered together. ### Claim 9 (depends on 5) The powder for the preparation of three-dimensional objects according to claim 5, wherein the biodegradable polymer is a homo- or copolymer prepared from monomers selected from the group of hydroxyalkanoates, lactic acid or derivatives thereof, caprolactone or derivatives thereof, glycolic acid or derivatives thereof, and combinations thereof.